Name: expression and purification of mammalian bestrophin ion channels
Uploaded: 2018-08-02T14:00:00
Description: Watch this Scientific Journal Video about Expression and Purification of Mammalian Bestrophin Ion Channels at JoVE.com

该项目由 NIH 赠款 EY025290、GM127652 和罗切斯特大学开办资金资助。

1. 产生 BacMam 表达杆状
<ol><li>将所需哺乳动物 bestrophin 蛋白的编码序列插入 pEG BacMam 向量18中, 用烟草蚀刻病毒 (TEV) 蛋白酶识别序列, 然后在蛋白质的 C 末端 GFP-10x 他的标记。</li>
	<li>瞬时染表达质粒成胶粘剂 HEK293 细胞19,20,21,22,23。用10X 或20X 放大倍数、488 ...

<ol>
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D., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bestrophin,+the+product+of+the+Best+vitelliform+macular+dystrophy+gene+(VMD2),+localizes+to+the+basolateral+plasma+membrane+of+the+retinal+pigment+epithelium.">Bestrophin, the product of the Best vitelliform macular dystrophy gene (VMD2), localizes to the basolateral plasma membrane of the retinal pigment epithelium.</a> Proceedings of the National Academy of Sciences of the USA. 97 (23), 12758-12763 (2000).</li><li>Marquardt, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mutations+in+a+novel+gene,+VMD2,+encoding+a+protein+of+unknown+properties+cause+juvenile-onset+vitelliform+macular+dystrophy+(Best's+disease).">Mutations in a novel gene, VMD2, encoding a protein of unknown properties cause juvenile-onset vitelliform macular dystrophy (Best's disease).</a> Human Molecular Genetics. 7 (9), 1517-1525 (1998).</li><li>Petrukhin, K., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Identification+of+the+gene+responsible+for+Best+macular+dystrophy.">Identification of the gene responsible for Best macular dystrophy.</a> Nature Genetics. 19 (3), 241-247 (1998).</li><li>Li, Y., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Patient-specific+mutations+impair+BESTROPHIN1's+essential+role+in+mediating+Ca2+-dependent+Cl-+currents+in+human+RPE.">Patient-specific mutations impair BESTROPHIN1's essential role in mediating Ca2+-dependent Cl- currents in human RPE.</a> eLife. 6, (2017).</li><li>Tsunenari, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure-function+analysis+of+the+bestrophin+family+of+anion+channels.">Structure-function analysis of the bestrophin family of anion channels.</a> Journal of Biological Chemistry. 278 (42), 41114-41125 (2003).</li><li>Kane Dickson, V., Pedi, L., Long, S. B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+and+insights+into+the+function+of+a+Ca(2+)-activated+Cl(-)+channel.">Structure and insights into the function of a Ca(2+)-activated Cl(-) channel.</a> Nature. 516 (7530), 213-218 (2014).</li><li>Yang, T., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Structure+and+selectivity+in+bestrophin+ion+channels.">Structure and selectivity in bestrophin ion channels.</a> Science. 346 (6207), 355-359 (2014).</li><li>Johnson, A. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bestrophin+1+and+retinal+disease.">Bestrophin 1 and retinal disease.</a> Progress in Retinal and Eye Research. , (2017).</li><li>Allikmets, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+the+Best+disease+gene+in+patients+with+age-related+macular+degeneration+and+other+maculopathies.">Evaluation of the Best disease gene in patients with age-related macular degeneration and other maculopathies.</a> Human Genetics. 104 (6), 449-453 (1999).</li><li>Burgess, R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biallelic+mutation+of+BEST1+causes+a+distinct+retinopathy+in+humans.">Biallelic mutation of BEST1 causes a distinct retinopathy in humans.</a> American Journal of Human Genetics. 82 (1), 19-31 (2008).</li><li>Davidson, A. E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Missense+mutations+in+a+retinal+pigment+epithelium+protein,+bestrophin-1,+cause+retinitis+pigmentosa.">Missense mutations in a retinal pigment epithelium protein, bestrophin-1, cause retinitis pigmentosa.</a> American Journal of Human Genetics. 85 (5), 581-592 (2009).</li><li>Kramer, F., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mutations+in+the+VMD2+gene+are+associated+with+juvenile-onset+vitelliform+macular+dystrophy+(Best+disease)+and+adult+vitelliform+macular+dystrophy+but+not+age-related+macular+degeneration.">Mutations in the VMD2 gene are associated with juvenile-onset vitelliform macular dystrophy (Best disease) and adult vitelliform macular dystrophy but not age-related macular degeneration.</a> European Journal of Human Genetics. 8 (4), 286-292 (2000).</li><li>Yardley, J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Mutations+of+VMD2+splicing+regulators+cause+nanophthalmos+and+autosomal+dominant+vitreoretinochoroidopathy+(ADVIRC).">Mutations of VMD2 splicing regulators cause nanophthalmos and autosomal dominant vitreoretinochoroidopathy (ADVIRC).</a> Investigative Ophthalmology &amp; Visual Science. 45 (10), 3683-3689 (2004).</li><li>Yang, T., Justus, S., Li, Y., Tsang, S. H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=BEST1:+the+Best+Target+for+Gene+and+Cell+Therapies.">BEST1: the Best Target for Gene and Cell Therapies.</a> Molecular Therapy. 23 (12), 1805-1809 (2015).</li><li>Boyce, F. M., Bucher, N. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Baculovirus-mediated+gene+transfer+into+mammalian+cells.">Baculovirus-mediated gene transfer into mammalian cells.</a> Proceedings of the National Academy of Sciences of the USA. 93 (6), 2348-2352 (1996).</li><li>Kost, T. A., Condreay, J. P., Jarvis, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Baculovirus+as+versatile+vectors+for+protein+expression+in+insect+and+mammalian+cells.">Baculovirus as versatile vectors for protein expression in insect and mammalian cells.</a> Nature Biotechnology. 23 (5), 567-575 (2005).</li><li>Goehring, A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Screening+and+large-scale+expression+of+membrane+proteins+in+mammalian+cells+for+structural+studies.">Screening and large-scale expression of membrane proteins in mammalian cells for structural studies.</a> Nature Protocols. 9 (11), 2574-2585 (2014).</li><li>Yang, T., He, L. L., Chen, M., Fang, K., Colecraft, H. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bio-inspired+voltage-dependent+calcium+channel+blockers.">Bio-inspired voltage-dependent calcium channel blockers.</a> Nature Communications. 4, 2540 (2013).</li><li>Yang, T., Hendrickson, W. A., Colecraft, H. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Preassociated+apocalmodulin+mediates+Ca2+-dependent+sensitization+of+activation+and+inactivation+of+TMEM16A/16B+Ca2+-gated+Cl-+channels.">Preassociated apocalmodulin mediates Ca2+-dependent sensitization of activation and inactivation of TMEM16A/16B Ca2+-gated Cl- channels.</a> Proceedings of the National Academy of Sciences of the USA. 111 (51), 18213-18218 (2014).</li><li>Yang, T., Puckerin, A., Colecraft, H. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Distinct+RGK+GTPases+differentially+use+alpha1-+and+auxiliary+beta-binding-dependent+mechanisms+to+inhibit+CaV1.2/CaV2.2+channels.">Distinct RGK GTPases differentially use alpha1- and auxiliary beta-binding-dependent mechanisms to inhibit CaV1.2/CaV2.2 channels.</a> Public Library of Science One. 7 (5), e37079 (2012).</li><li>Yang, T., Suhail, Y., Dalton, S., Kernan, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Genetically+encoded+molecules+for+inducibly+inactivating+CaV+channels.">Genetically encoded molecules for inducibly inactivating CaV channels.</a> Nature Chemical Biology. 3 (12), 795-804 (2007).</li><li>Yang, T., Xu, X., Kernan, T., Wu, V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Rem,+a+member+of+the+RGK+GTPases,+inhibits+recombinant+CaV1.2+channels+using+multiple+mechanisms+that+require+distinct+conformations+of+the+GTPase.">Rem, a member of the RGK GTPases, inhibits recombinant CaV1.2 channels using multiple mechanisms that require distinct conformations of the GTPase.</a> Journal of Physiology. 588 (Pt 10), 1665-1681 (2010).</li><li>Kawate, T., Gouaux, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fluorescence-detection+size-exclusion+chromatography+for+precrystallization+screening+of+integral+membrane+proteins.">Fluorescence-detection size-exclusion chromatography for precrystallization screening of integral membrane proteins.</a> Structure. 14 (4), 673-681 (2006).</li><li>Schmidt, C., Urlaub, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combining+cryo-electron+microscopy+(cryo-EM)+and+cross-linking+mass+spectrometry+(CX-MS)+for+structural+elucidation+of+large+protein+assemblies.">Combining cryo-electron microscopy (cryo-EM) and cross-linking mass spectrometry (CX-MS) for structural elucidation of large protein assemblies.</a> Currents Opinions in Structural Biology. 46, 157-168 (2017).</li><li>Sun, W., Zheng, W., Simeonov, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Drug+discovery+and+development+for+rare+genetic+disorders.">Drug discovery and development for rare genetic disorders.</a> American Journal of Medical Genetics Part A. 173 (9), 2307-2322 (2017).</li></ol>

该协议描述了一种有用的管道, 用于表达和纯化哺乳动物 bestrophin 离子通道, 用于未来的体外分析。虽然 FPLC 设备是需要的大小排除色谱, 注射器泵是足够的所有步骤的亲和层析, 包括捆绑, 洗涤和洗脱。当使用注射器泵来推动溶液 (在注射器中) 通过一列, 这是必不可少的垫弹簧一侧, 以避免推动气泡进入柱。如果蛋白质的纯度在亲和层析后已经足够的后续实验, 大小排除色谱可以省略, 以便 FP...

Bestrophins 是一个通过从细菌到人类的不同物种而保存的离子通道的家族1。在人类中, BEST1基因, 位于染色体 11q12.3, 编码的膜蛋白 Bestrophin-1 (BEST1), 主要表现在基底膜的视网膜色素上皮 (RPE) 细胞的眼睛2,3 ,4。由585种氨基酸组成, 其中第一 ~ 350 在物种间高度保守, 含有其跨膜区域, BEST1 在人类1、5、6中起 CaCC 作用。此外, 鸡和肺炎克雷伯杆菌的 BEST1 同系物的作用为 homopentamers7,8, 表明整个进化过程中的保护水平很高。
在人类中, BEST1基因的200多个突变已经临床上与一组称为 bestrophinopathies1,9的视网膜变性疾病有关。报告了五项具体 bestrophinopathies, 包括最佳疾病、成人发病 vitelliform 营养不良、常染色体显性 vitreoretinochoroidopathy、常染色体隐性 bestrophinopathy 和视网膜色素变性3、4 ,10,11,12,13,14。这些疾病, 导致视力下降, 甚至失明, 目前无法治愈。为了发展治疗治疗和潜在的个性化医学, 重要的是要了解这些BEST1疾病引起的突变如何影响 BEST1 通道15的功能和结构。为了这些目的, 研究人员需要获得纯化的 bestrophin (野生类型和/或突变) 通道, 并进行体外分析5,8。
第一个关键步骤是哺乳动物细胞中较高物种的 bestrophin 通道的表达。由于 HEK293-F 细胞的杆状病毒转导 (BacMam 系统) 是 heterologously 表达膜蛋白16、17的一种强有力的方法, 该协议利用优化的 BacMam 向量 (pEG BacMam) 进行鲁棒表达。靶蛋白18, 在这种情况下是哺乳动物 bestrophin 同源。该载体用于各种膜蛋白的表达, 包括 G 蛋白偶联受体、核受体和其他离子通道18。还有证据表明, 所生产的蛋白质适合晶体学18。在 HEK293-F 细胞中具有较高的表达水平, 可以用色谱法纯化蛋白质;具体地说, 在 bestrophins 的情况下, 可以使用亲和性和大小排除色谱。
一旦该协议对 bestrophin 通道进行微调, 则可以通过平面脂质双层和 X 射线晶体学分别对纯化后的蛋白质进行分析, 以5、8为其功能和结构。总之, 这些技术为 bestrophins 和其他离子通道的功能和结构研究提供了强有力的管道。

<table border="0" cellpadding="0" cellspacing="0" width="680">
	<tbody>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">HEPES</td>
			<td style="width:148px;">Fisher Scientific</td>
			<td style="width:119px;">AC327265000&#160;</td>
			<td style="width:197px;"></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">NaCl</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">AC446212500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Glycerol</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">G33-500</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Imidazole</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">AC301870010</td>
			<td></td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;width:216px;">MgCl2</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">AC197530010&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">TCEP</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">AA4058704&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Aprotinin</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">AAJ63039MA</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Leupeptin</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">AAJ61188MB&#160;</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Pepstatin A</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">AAJ20037MB</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Phenylmethylsulfonyl fluoride</td>
			<td>Fisher Scientific</td>
			<td style="width:119px;">AC215740050</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">DDM sol-grade</td>
			<td style="width:148px;">Anatrace</td>
			<td style="width:119px;">D310S</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">DDM anagrade</td>
			<td style="width:148px;">Anatrace</td>
			<td style="width:119px;">D310</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Sf-900 II SFM</td>
			<td style="width:148px;">ThermoFisher</td>
			<td style="width:119px;">10902179</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">FreeStyle medium</td>
			<td>ThermoFisher</td>
			<td style="width:119px;">12338018</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">NanoDrop spectrophotometer</td>
			<td>ThermoFisher</td>
			<td style="width:119px;">ND-2000</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">High pressure homogenizer</td>
			<td style="width:148px;">Avestin</td>
			<td style="width:119px;">Emulsiflex-C5</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">HisTrap column</td>
			<td style="width:148px;">GE</td>
			<td>17-5248-01</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Superdex-200 column</td>
			<td style="width:148px;">GE</td>
			<td style="width:119px;">28990944</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">AKTA Pure</td>
			<td style="width:148px;">GE</td>
			<td style="width:119px;">29018224</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Ultra-15 centrifugal filter units</td>
			<td style="width:148px;">Millipore</td>
			<td style="width:119px;">UFC910024</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Ultra-4 centrifugal filter units</td>
			<td style="width:148px;">Millipore</td>
			<td style="width:119px;">UFC810024</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Ultra-0.5 centrifugal filter units</td>
			<td style="width:148px;">Millipore</td>
			<td style="width:119px;">UFC505024</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Optima XE-90 Ultracentrifuge</td>
			<td style="width:148px;">Beckman Coulter</td>
			<td>A94471</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Mini-PROTEAN Tetra Cell</td>
			<td style="width:148px;">Bio-Rad</td>
			<td>1658004</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">Mini-PROTEAN precast gel</td>
			<td style="width:148px;">Bio-Rad</td>
			<td>4561084</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">T100 Thermal Cycler</td>
			<td style="width:148px;">Bio-Rad</td>
			<td>1861096</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">PolyJet transfection reagent</td>
			<td style="width:148px;">SignaGen</td>
			<td>SL100688</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;width:216px;">pEG BacMam vector</td>
			<td style="width:148px;"></td>
			<td style="width:119px;"></td>
			<td>Obtained from the Gouaux lab at Vollum Institute</td>
		</tr>
	</tbody>
</table>

expression and purification of mammalian bestrophin ion channels

人类基因组编码四 bestrophin paralogs, 即 BEST1、BEST2、BEST3 和 BEST4。BEST1, 编码的BEST1基因, 是一个 Ca2 +激活 Cl 通道 ( CaCC) 主要表现在视网膜色素上皮 (RPE)。BEST1 的生理和病理意义被强调的事实是, 在BEST1基因的200多个不同的突变已经基因链接到至少五视网膜退行性疾病的频谱, 如最佳 vitelliform黄斑营养不良 (最佳疾病)。因此, 了解 bestrophin 通道在单分子水平上的生物物理学具有重要的意义。然而, 获得纯化的哺乳动物离子通道往往是一项具有挑战性的任务。在这里, 我们报告了哺乳动物 bestrophin 蛋白的表达与 BacMam 杆状病毒基因转移系统和他们的亲和性和大小排斥色谱纯化的协议。纯化蛋白在随后的功能和结构分析中有潜在的应用前景, 如脂质双层和晶体学中的电生理记录。重要的是, 这条管道可以适应研究其他离子通道的功能和结构。

瞬态转染胶粘剂 HEK293 细胞的荧光强度 (图 1A) 是悬浮 HEK293-F 细胞中预测蛋白表达水平的良好指标 (图 1B)。如果靶蛋白在瞬态转染后在 HEK293 细胞中表达不良好或被错误地定位, 建议考虑修改表达结构 (例如, 改变 GFP 标记的位置或做出突变/截断目标蛋白)。小 HEK293-F 悬浮培养 (例如, 25 毫升培养) 用于优化蛋白质表达?...

Watch this Scientific Journal Video about Expression and Purification of Mammalian Bestrophin Ion Channels at JoVE.com

Expression and Purification of Mammalian Bestrophin Ion Channels

哺乳动物 Bestrophin 离子通道的表达与纯化

离子通道的纯化往往具有挑战性, 但一旦达到, 它就有可能允许对通道的功能和结构进行体外调查。在这里, 我们描述的步骤, 以表达和纯化哺乳动物 bestrophin 蛋白, 一个家庭的 Ca2 +激活 Cl 通道.

The human genome encodes four bestrophin paralogs, namely BEST1, BEST2, BEST3, and BEST4. BEST1, encoded by the BEST1 gene, is a Ca2+-activated Cl- ...

Research

JoVE Journal

Biochemistry

Thermostabilization, Expression, Purification, and Crystallization of the Human Serotonin Transporter Bound to S-citalopram

Thermostabilization, Expression, Purification, and Crystallization of the Human Serotonin Transporter Bound to S-citalopram

热稳定，表达，纯化，和人类血清素转运蛋白结晶绑定到<em&gt;取值</em&gt; -citalopram

The serotonin transporter is a sodium and chloride-coupled transporter that &#34;pumps&#34; extracellular serotonin into cells. S-citalopram is a drug ...

科研

生物化学

Expression, Purification, and Antimicrobial Activity of S100A12

S100A12的表达，纯化和抗菌活性

Calgranulin proteins are important mediators of innate immunity and are members of the S100 class of the EF-hand family of calcium binding proteins. Some ...

Measurement of Ion Concentration in the Unstirred Boundary Layer with Open Patch-Clamp Pipette: Implications in Control of Ion Channels by Fluid Flow

开放补丁夹具移液器测量未搅拌边界层中的离子浓度: 流体流动对离子通道控制的启示

Fluid flow is an important environmental stimulus that controls many physiological and pathological processes, such as fluid flow-induced vasodilation. ...

Expression and Purification of the Human Lipid-sensitive Cation Channel TRPC3 for Structural Determination by Single-particle Cryo-electron Microscopy

单粒子冷冻电子显微镜在结构中测定脂质敏感分通道 trpc3 的表达与纯化

Transient receptor potential channels (TRPCs) of the canonical TRP subfamily are nonselective cation channels that play an essential role in calcium ...

Expression, Solubilization, and Purification of Eukaryotic Borate Transporters

真核硼酸背液转运体的表达、增溶及纯化

The Solute Carrier 4 (SLC4) family of proteins is called the bicarbonate transporters and includes the archetypal protein Anion Exchanger 1 (AE1, also ...

Expression and Purification of Nuclease-Free Oxygen Scavenger Protocatechuate 3,4-Dioxygenase

无核酸酶的表达和纯化原氧基质 3，4-二氧酶

Single molecule (SM) microscopy is used in the study of dynamic molecular interactions of fluorophore labeled biomolecules in real time. However, ...

Expression, Purification, Crystallization, and Enzyme Assays of Fumarylacetoacetate Hydrolase Domain-Containing Proteins

富玛莱酸氢酶含含蛋白质的表达、纯化、结晶和酶测定

Fumarylacetoacetate hydrolase (FAH) domain-containing proteins (FAHD) are identified members of the FAH superfamily in eukaryotes. Enzymes of this ...

PCR Mutagenesis, Cloning, Expression, Fast Protein Purification Protocols and Crystallization of the Wild Type and Mutant Forms of Tryptophan Synthase

PCR 突变体、克隆、表达、快速蛋白质纯化协议和色氨酸合成酶野生类型和突变形式的结晶

Structural studies with tryptophan synthase (TS) bienzyme complex (&#945;2&#946;2 TS) from Salmonella typhimurium have been performed to better understand ...

Ganglioside Extraction, Purification and Profiling

神经节苷脂提取、纯化和分析

Gangliosides are glycosphingolipids that contain one or more sialic acid residues. They are found on all vertebrate cells and tissues but are especially ...

Efficient and Scalable Production of Full-length Human Huntingtin Variants in Mammalian Cells using a Transient Expression System

Full-length huntingtin (FL HTT) is a large (aa 1-3,144), ubiquitously expressed, polyglutamine (polyQ)-containing protein with a mass of approximately 350 ...